Islanders are older, more racially diverse and live in slightly smaller households with fewer children, according to some of the latest data released by the US Census Bureau Wednesday night.

Mercer Island mirrored the aging of King County and the State of Washington as the median age on the Island rose to 46 years old in 2010, up from 44.3 in 2000 (see data table below for age and demographic information detailed in this story).

The Island is also significantly more diverse, with the largest increase coming from 1,000 new residents since 2000 identifying themselves as "Asian". The current total of 3,615 makes their group the community's largest minority population at 15.9 percent of all residents. The increase was driven by significant increases in ethnically Chinese, Asian Indian and Korean populations, while Mercer Island's traditional Japanese community saw a small decline. The Island's largest population by race, "White", declined by over 800 residents. .

Islanders were also less likely to have children in 2010 as the number of households increased but the number of children under 18 years-old dropped. Of the 9,109 households counted — an 8 percent increase from a decade ago — 6,532 identified themselves as families but only 2,979 reported children living with them — 15 fewer than in 2000. The average size of households also declined to less than three people, down from 3.03 to 2.97.

The local gender gap also decreased slightly, with 48.7 percent of Island residents male (48.1 in 2000) and 51.3 percent female (51.9 in 2010). Women on Mercer Island also live longer then men, with a median age of 46.8 years. 

The primary intent of US Census data is to fulfill the mandate set forth in Article 1, Section 2 of the US Constitution to count all residents where they live in order to represent them proportionately with elected officials to Congress — but the agency collects additional information by law. based on the 2010 Census data.

Statewide, the median age was 37.3 in 2010, up from 35.3 in 2000, and the percentage of males to females was the same, 49.8 percent to 50.2 percent.

Some additional statewide figures include:

• The median age for males was 36.2 and 38.3 for females last year, up from 34.4 for males and 36.3 for females in 2000. 
• The average household size was 2.51 people, nearly flat from 2.53 in 2000.
• The average family size was 3.06, about the same as 3.07 in 2000.

But looking at households, families made up 64.4 percent in 2010, down from 66 percent 10 years ago. And of those family households, those with their own children under 18 dropped from 32.7 percent to 29.1 percent.

At the same time, the state's proportion of other relatives living in households jumped considerably. In 2000, the Census counted 236,631 "other relatives" living in all households, or 4 percent of the population. Ten years later, that grew to 349,380, or 5.2 percent -- a 30 percent jump in the proportion.

Other data released Wednesday:
King County:
Median age: 37.1 (2000: 35.7)
Males 49.8 percent, females 50.2 (2000: unchanged)
Median age by gender: males 36.3, females 37.9 (2000: males 34.9, females 36.6)
Average household size: 2.40 (2000: 2.39)  
Average family size: 3.05 (2000: 3.03)

 

Mercer Island By the Numbers

Selected Demographics Mercer Island Number 2000 Percent 2000 Number 2010 Percent 2010 Total population 22,036 100.0 22,699 100 SEX           Male 10,598 48.1 11,046 48.7     Female 11,438 51.9 11,653 51.3 AGE           Under 5 years 997 4.5 1,009 4.4     5 to 9 years 1,644 7.5 1,565 6.9     10 to 14 years 1,930 8.8 1,788 7.9     15 to 19 years 1,530 6.9 1,645 7.2     20 to 24 years 550 2.5 683 3.0     25 to 34 years 1,366 6.2 1,592 7.0     35 to 44 years 3,306 15.0 2,712 12.0     45 to 54 years 4,014 18.2 3,982 17.5     55 to 59 years 1,465 6.6 1,819 8.0     60 to 64 years 1,120 5.1 1,481 6.5     65 to 74 years 1,962 8.9 2,009 8.8     75 to 84 years 1,577 7.2 1,548 6.8     85 years and over 575 2.6 866 3.8     Median age (years) 44.3 (X) 46.0  ( X ) RELATIONSHIP           Total population 22,036 100.0 22,699 100.0     In households 21,757 98.7 22,631 99.7       Householder 8,437 38.3 9,109 40.1       Spouse 5,538 25.1 5,671 25.0       Child 6,721 30.5 6,690 29.5         Own child under 18 years 5,578 25.3 5,432 23.9       Other relatives 446 2.0 485 2.1         Under 18 years 107 0.5 114 0.5       Nonrelatives 615 2.8 676 3.0         Unmarried partner 181 0.8 313 1.4     In group quarters 279 1.3 68 0.3       Institutionalized population 139 0.6 43 0.2       Noninstitutionalized population 140 0.6 25 0.1 HOUSEHOLDS BY TYPE           Total households 8,437 100.0 9,109 100.0     Family households (families) 6,273 74.4 6,532 71.7       With own children under 18 years 2,994 35.5 2,979 32.7   Husband-wife family 5,538 65.6 5,671 62.3         With own children under 18 years 2,547 30.2 2,475 27.2       Female householder, no husband present 564 6.7 596 6.5         With own children under 18 years 345 4.1 350 3.8     Nonfamily households 2,164 25.6 2,577 28.3       Householder living alone 1,861 22.1 2,198 24.1     Households with individuals under 18 years 3,077 36.5 3,051 33.5     Households with individuals 65 years and over 2,676 31.7 3,036 33.3     Average household size 2.58 (X) 2.48  ( X )     Average family size 3.03 (X) 2.97  ( X )